Haloacetic Acids as Corrosion Inhibitors for Brass in Nitric Acid Available to Purchase

The effect of chloro, dichloro, trichloro, bromo, and iodoacetic acids on corrosion of brass in dilute nitric acid has been studied using weight loss and polarization techniques. A significant retardation of the corrosion rate is observed in the inhibited nitric acid. The rate of corrosion depends on the nature of the inhibitor and its concentration, temperature of the system, stirring rate of the solution, and the concentration of the nitric acid. The values of inhibitor efficiency from weight loss measurements are in good agreement with those obtained from polarization studies. The drift of corrosion potential towards less noble direction and the change in cathodic Tafel slope indicate that haloacetic acids act as cathodic inhibitors for brass in nitric acid. The thermodynamic parameters of adsorption obtained using Bockris-Swinkels adsorption isotherm reveal a strong interaction of these inhibitors on brass surface.